1. Field of the Invention
The present invention relates to a plug, particularly to a power plug.
2. The Related Art
U.S. Pat. No. 6,595,782 issued on Jul. 22, 2003 discloses a conventional power plug. The conventional power plug normally has a housing, at least two connecting blades, at least two disks securely received in the housing, at least two slip rings each mounted on one of the two disks and power relative to the corresponding disk, and at least two securing elements each received in the housing to securely engage with the corresponding slip ring. After the two slip rings are securely connected to the securing elements and the two connecting blades are electrically connected to the two disks, the plug is able to rotate regardless of the connection between the two connecting blades and a power socket firmly fixed at a location.
The rotation of the power plug in this patent is accomplished between the slip ring and the collector ring. The collector ring, the slip ring and the insulator bring about different friction effects. Since the contact area of the friction is too wide, it will reduce the life of a frequently used plug, and may compromise the quality of life.
To overcome these shortcomings, the present invention tends to provide an improved plug which permits a reduction of friction between the collector ring and the slip ring to mitigate and obviate the aforementioned problems.